Motor operated switch



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Sept. 27, 1949. J. F. FRESE MOTOR OPERATED SWITCH l1 Sheets-Sheet 11Original Filed April 27, 1944 INVENTOR- Eaoay? if, naw,

Patented Sept. 27.1949

2,482,757 MOTOR OPERATED SWITCH Joseph F. Frese, Baltimore, Md.,assignor to The Monitor Controller mpany,

Baltimore, Md.,

a corporation of Maryland Original application April 27, 1944, SerialNo.

Divided and this 1945, Serial No. 597,763

3 Claims. (Cl. 200-92) My invention relates broadly to electricalswitches and more particularly to an automatically operated electricswitch system.

This application is a division of my application Serial Number 533,010,filed April 27, 1944, for Automatic electric switch and contactorsystem.

One of the objects of my invention is to provide an arrangement ofspring driven electric switch which may be instantaneously actuated byrendering the spring effective to drive the switch.

Another object of my invention is to provide a remotely controlledautomatic switch that may be opened and/or closed under control of aspring motor which is conditioned from time to time by an electricmotor.

Another object of my invention is to provide an arrangement of highpotential switch which may be moved to open or closed position undercontrol of a spring driven motor at uniform speed where the springdriven motor is wound from time to time under control of an electricmotor.

Still another object of my invention is to provide a construction ofspring governed switch having an electric motor winding deviceassociated therewith and in which a multiplicity of coa'cting auxiliarycontacts are controlled synchronously with the operation of the switch.

A still further object of my invention is to provide a construction ofelectric switch in which a pair of switch arms may be automaticallymoved in opposite directions simultaneously under control of a springmotor actuator for opening and/0r closing electric circuits.

Still another object of my invention is to provide a construction ofspring operated actuator for driving the arms of an electric switchsystem where the spring operator is wound from time to time as requiredby an electric motor.

A further object of my invention is to provide a construction ofauxiliary contact system operated by cam devices controlled by themovement of the electric switch system of my invention.

Still another object of my invention is to provide a high potentialswitch system including insulators for mounting angularly movable armshaving contactors thereon'in combination with mechanism for movin thearms in clockwise and counter-clockwise directions for makin andbreaking connection with stationary contacts insulatedly mounted inalignment with theswitch arms;

Still another object of my invention is to provide a construction ofreverse drive mechanism for a pair of electric switches with means forsimultaneously moving t e electr c switc s n application June 6,

opposite directions with respect to each other for making or breakingcoacting electric/a1 connections.

Other and further objects of my invention reside in the construction andarrangement of parts of the automatic switch as set forth in theaccompanying specification and shown in the accompanying drawings inwhich:

Figure 1 is a plan view of the automatic switch system and actuatortherefor; Fig. 2 is a top plan view of the automatic switch system anddrive therefor; Fig. 3 is'a side view of the automatic switch system andactuator; Fig. 4 is a view illustrating the arrangement of auxiliarycontacts in association with one of the switch arms and illustratingthe-automatic drive control mechanism in association therewith; Fig. 5is a plan view showing one of the switch arms carried by the insulator;Fig. 6 is an end view of the hardware which supports the switch arm withrespect to the insulator; Fig. 7 is a cross sectional view through thehardware and insulator showing the support of the switch arm thereby;Fig. 8 is a transverse sectional view taken on line 88 of Fig. 4illustrating the stationary contact which is carried by an insulatormounted on the apparatus panel; Fig. 9 is a plan view showing theauxiliary contacts and the arrangement of cams for controlling thecontacts synchronously with the movement of the switch arm; Fig. 10 is alongitudinal sectional view through the cam control mechanism for theauxiliary contacts; Fig. 11 is a detailed elevational view of one of thecams formed from insulation material for actuating the auxiliarycontacts; Fig. 12 is an end view of the cam illustrated in Fig. 11; Fig.13 is a top plan view of the auxiliary contacts and actuating camsassociated therewith; Fig. 14 is a longitudinal sectional view throughthe auxiliary contact system; Fig. 15 is a detailed sectional viewshowing the arrangement of one of the contactors of the auxiliarycontacts; Fig. 16 is a detailed view of one of the auxiliary contactsshowing the method of establishing electrical connection therewith; Fig.17 is an end view illustrating the arrangement of the auxiliary contactsand the cam actuator for controlling the contacts; Fig. 18 is atransverse sectional view with certain of the parts illustrated in sideelevation taken on line |8l8 of Fig. 10; Fig. '19 is an elevational viewof one of the movable sections of the auxiliary contact system; Fig. 20is a transverse sectional view taken on line 20-40 of Fig; 19; Fig. 21is a transverse sectional view taken on line 21-21 of Fig. 19; Fig 22 isan end view looking in the direction of assays? 3 arrow A in Fig. 19;Fig. 23 is an end view of the switch actuator for eflecting rapidoperation of the automatic switch; Fig. 24 is a transverse sectionalview through the case taken on line 24-24 of Fig. 29, the view beingpartially broken away;

Fig. 25 is a fragmentary composite sectional and elevational view of thefloating connection between the bell crank and brake actuatingdever;Fig. 26 is a detailed view of the brake actuating arm; Fig. 2'7 is adetailed view of the brake applicator arm; Fig. 28 is an end view of thearm shown in Fig. 21'; Fig. 29 is a transverse sectional view takensusbtantially on line 23-23 of Fig. 31; Fig. 30 is a transversesectional view taken substantially on line 30-30 of Fig. 31; Fig. 31 isa view showing the relative arrangement of the power spring and thespring winding mechanism taken substantially on line 3| 3| of Fig. 23;Fig. 32 is a plan view of one of the drums employed in driving theswitch arms showing the adjustable members thereof; Fig. 33 is an endview of the drum shown in Fig. 32; Fig. 34 is a fragmentary sectionalview illustrating how the driving band is adjustably held in place; Fig.35 is an end view of the coacting drum which connects with the drivingbands for driving the switch arms; Fig. 36 is a fragmentary sectionalview taken on line 36-36 of Fig. 35 showing the method of fastening theopposite ends of the bands that are fixedly secured on drum 34 andadjustably secured on drum 50; Fig. 37 is a view of one of the adjustingscrew terminus members secured to the end of the driving band; Fig. 38is a plan view of one of the actuating cams employed in the switchactuating mechanism; Fig. 39 is a side elevational view of the cam shownin Fig. 38 and Fig. 40 is a schematic view of the switch system of myinvention illustrating one arrangement of circuit system to which theautomatic switch may be applied.

Referring to the drawings in detail reference characters I and 2designate the switch arms which are carried in fittings 3 and 4respectively carried on the insulators and i. The manner of securing thearms to the insulators is shown more particularly in Figs. 5, 6 and 7wherein it will be seen that the hardware 3 and 4 are recessed asindicated at I to fit over the metallic cap member 8 which is secured bya suitable coating of cement or metallic layer indicated at 3 t0 the endof the insulator. The cap 3 has a projection I ll thereon which iscentrally recessed and screw-threaded at H to receive the screw-threadedmember 12 which forms the connection means for the flexible cable l4constituting the electrical connection for the switch arm. Set screws l3extend through threaded apertures in the hardware 3 and 4 and engage theprojecting end of the metallic cap at III for firmly securing the switcharm in position with respect to the insulator 5. The hardware fittings 3and 4 contain arcuate shaped lipped portion Ii through which a set screwit may extend for locking the hexagonal head I l of the screw-threadedterminal member l2 of the flexible cable H for insuring firm position ofthe switch arm with respect to the insulator 5. The switch arms carry attheir ends spring contact members which I have illustrated at I8 and I9shaped to present fiat parallel faces to the coacting jaws of the fixedcontacts and which are secured to opposite portions of the switch arm.The faces of contacts l3 and ll are silvered to insure good conductivityunder conditions of arcing when establishing connection with thecoacting faces of the coacting switch 4 laws. The switch arm is slottedthroughout a portion of its length as represented at 23 to impartsufllcient resiliency to the contact members is and I9 and thus insuregood electrical contact when the contact members II and I3 engagebetween the laws 21 and Ila ci'the fixed contactor represented at 22.Conditions of vibration are thereby prevented from displacing ordisturbing the contact so that the switch system is applicable in anyplace subject to vibration. The op- ,posite Jaws 2i and 21a have theirinterior faces coated with a silver lining 2 I and 2 la to increaseconductivity. The means for securing hardware 22 constituting thestationary contact with respect to the insulator are identical with themeans for securing the hardware 3 and 4 constituting the support for themovable contactor or switch arm in order to facilitate production andreduce manufacturing and maintenance costs. The number of replacementparts may thereby be maintained at a minimum. Electrical connection isestablished with the fixed contact in any suitable manner such as themethod explained in connection with the movable contact or through a lugand screw arrangement designated generally at 23. Securing means Ilasimilar to the securing means I: for the hardware associated with themovable switch arm are employed for securing the stationary hardwarewith respect to insulator 6.

' I have described the switch arm construction for one of the switchesin detail and it will be understood that the other arm is constructed ing a similar manner .and that corresponding reference characters indicatesimilar parts. I have illustrated my invention applied to a two-polesingle throw switch, but it will be fully understood that theconstruction may be applied to a double throw system or multiple contactarrangement.

The insulators i and 6 are movable with respect to a panel representedat 24 which provides mounting means for the automatic switch operatlngmechanism, the auxiliary contact system, the driving motor and the motorcontrol mechanism.

Stationary contactor 22 carried by insulator I31 is mounted directlyupon the panel by the socket base 2!. Socket base 25 is suitably securedby flange bolts 26 to panel 24. The movable insulators 5 and 8 are eachsupported as illustrated in Figs. 9 and 10. Insulator 5 is secured in asocket member 21 which is secured in any suitable manner to the fiangemember 23 carried by the shaft 23. Shaft 23 is journaled in sleevebearing 34. The sleeve bearing 30 is oilless and does not requirelubrication. It is supported in housing 3| which forms part of the basecasting 32 secured to the panel by through bolts represented at 33. Thesleeve bearing 33 extends the (all length of the housing 3| whichterminates in a position forming an abutment for the hub portion 32 ofthe drum 34. Drum 34 has two peripheral grooves 35 and 3! within whichthe driving bands 31 and 33 operate. Drum 34 also carries stud bolts 33,43 and 4i each of which include spacing sleeves 33a, 43a and 4Iathereon. The spacing sleeves serve as supporters for the cam membersrepresented at 42, 43 and 44 shaped as illustrated in Figs. 11 and 12.The end members of each of the stud bolts are formed from insulationmaterial represented at 33b to insure against electrical breakdownbetween the metallic casting or housing 32 and the stud bolt fasteningscrews indicated at Me. Similar insulated end members ary contacts.

are provided on the coactlng stud bolts. The

cams are supported at spaced peripheral distance by the three stud bolts39, 48 and 4i as shown more particularly in Fig. 18. These cams eachhave preformed faces thereon represented at 42a, 43a and 44a serving asactuators for the mow able auxiliary switch contact arms shown at 45, 46and 41. The movable auxiliary contact arms each carry pairs of rollermembers formed from insulation material represented at 46a and 46b whichroll over the cam surface of the coacting actuator cam for moving theswitch arm about its central pivot illustrated at 45c for rocking theswitch arm into either the law contacts 46d or jaw contacts 45c. Theactuating rollers carried by the auxiliary switch arms are representedmore clearly at 45a, 46a and 41a in Fig. 9 operative with the respectivecam surfaces 42a, 43a and 44a. The sets of stationary contacts are shownin Fig. 9 at 45d, 46d and 41d. The arrangement of the stationarycontacts is illustrated in Fig. from which it will be seen that eachstationar contact is formed by a pair of spaced parallel extendingmetallic plates 45! to which the contact members constituting thestationary contacts 4541 are riveted or otherwise secured. A connectingmember in the form of a block 45g is disposed between the parallelplates 45) and includes a terminal screw 45h therein for establishinconnection with the sets of contacts 45d. This same arrangement isrepeated for the center support of the contact arm 45 at 45i and theopposite set of contacts 456 at 457'. It will be understood that thesets of stationary contacts and the center support for the switch armare constituted by separate metallic plate members 45f secured toopposite sides of the strip of insulation shown at 48 which extendsbetween the limits which I have indicated at 45k and 451.

Each of the sets of stationary and auxiliary contacts include separatemounting means for the switch arms and separate terminals for thecenters of the switch arms and for the sets of contacts with which theswitch arms are arranged to coact.

The drum shown at 34 coacts with a drum 56 which is associated with themovable, shaft 6. Drum 50, however, is formed differently than drum 34as represented more particularly in Figs. 31, 32 and 33 as provision ismade for the tightenlng of the bands and the adjustment of contact arm 6in order to insure proper alignment of the switch arms with respect tothe station- Drum 58 contains annular grooves 5| and 52 with lugsextending into the path thereof represented at 53 and 54 respectivelyaround a chordal portion 55 of the drum. Each of the lugs is aperturedto receive adjustably screw-threaded bolt members 56 shown moreparticularly in Fig. 36. The bolt members 56 are bifurcated at theirends and are attached to the bands shown at 31 and 38. The opposite endsof the bands 31 and 38 terminate under screwheads 51 and 58 engageablein the periphcry of drum 84 as illustrated in Figs. 34 and 35. It willbe observed that the ends of the bands 31 and 38 are reinforced asrepresented, for example, at 31a to enable them to be secured under thesecuring screws such as 51 and 68 in drum 34 and allow precise controlof effective length. The adjustment is made by tightening or looseningthe adjusting nuts 56a on the coacting screw-threaded bolt member suchas 66 in Fig. 33. Thus adjustabilit may be effected on drum 50 whilepermanent connections are es- 6-8 terminating in v oscillation through 6tablished on drum 34. The drum 34 is provided with screw-threadedopenings into which fastening screws 89 may be inserted for securingbracket member 60 in position. Bracket member 60 with the drum 34 onwhich it is mounted constitute a crank by means of which the rotationthrough 180 of the shaft 61 is changed to a smaller angle of the shaft26. Shaft 61 has discs 62 and 63 mounted thereon. The discs 62 and 63are shown more particularly in Figs. 3,- 4, 23, 31, 38, 39 and 40. Discs62 and 63 have notches therein which engage to hold the shaft 61 onwhich they are mounted from rotation.

There are two discs as shown clearly in Fig. 40, one of which is shownat 62 and the other of which is shown at 63. Discs 62 and 63 are exactopposites of each other and have opposite actuating faces 62b and 63b.The link 6| is pivotally connected to the stud bolt 64 which is pivotedin disc '63 but passes loosely through disc 62 as clearly shown in Fig.4. The two discs are mounted on shaft 65 which has two flat portions 66,one on each side thereof. One disc 62 is recessed at 68 to receive thehead of the retaining screw 69 which connects to the tapped portion ofshaft 65. The two discs 62 and 63 also have internal flat faces shown at62a and 63a respectively to engage upon the coacting flat faces of theprojecting end of the shaft 65 thus keying or looking the discs 62 and63 to rotate fast with the extension of shaft 65 shown at 61. Extensionshaft 61 extends transversely of the casing 68 and is journaled thereinat opposite ends represented at 69 and 18. The bearing 10 is supportedin the base plate ll carried on the upper section of casing. 68 byspacer members indicated at 12 held in place by screws 12a.

The shaft 67 thus journaled has an enlarged section which isscrew-threaded which is represented at 13. Below the screw-threadedsection 13 are two flats represented at 14 on which there is mounted acam 15 which turns with the shaft 61. A traveling nut 16 is arranged tomove over the screw-threads 13 and traverses a path extending parallelwith the shaft guided by two studs I1 and 18 which pass through coactingapertures in traveling nut 16'. On traveling nut 16 there is carried aprojecting cam face 19 which is arranged to coact with face 86 of thecam 15 when the nut approaches its screw-threads 13 to restrict theunwinding of the spiral spring 85. The studs 11 and 18 are carried byworm gear 8| as shown. The base portions of the mounting means for studs11 and 18 are cutaway at "a and 16a to allow clearance for the cam 15.The worm gear 8i has a sleeve portion 83 rotatably mounted on shaft 61'within the spring case shown at 84. The spring case 84 houses flatspiral spring 85 which is secured at one end to the case 84 and at theopposite end to the sleeve 83. The bushing 81 of the spider gear wheelI32 is pinned to the shaft 61 as represented at 88. The spider gearwheel I32 forms one end of the spring case 84. The spring case 84remains stationary while spring 85 is being wound.

The manner of winding the spring 85 will be more clearly understood byconsidering the arrangement of the driving motor 89 which is sup portedon panel 24. Motor 88 may be of any desired type for driving shaft 96through suitable coupling 9| which connects to shaft 92 Journaled inbearing 93 in the side wall of easing pinion 94. Pinion 94 engages limitof travel on with the gear 95 which is carried by shaft 88. Shaft 86 isjournaled in bearings 91 and 88 in opposite ends of the casing 68 andcarries worm gear 93 thereon which engages with the worm wheel 8|. Thusthe driving motor 89 is enabled to rotate sleeve 83 which is connectedto spiral spring 85 for winding spiral spring 85 within spring case 84.During this winding operation the traveling nut I6 moves away from thecam I5 on screw-thread I3 and at the limit of its travel engages pin Iwhich acts upon arm IOI. Arm IOI 'is pivoted on block I02 on theexterior of casing 68. An extension I03 on arm IN is operated to engageoperating member I03 of micro-switch I 04. Micro-switch I0 is arrangedin the motor circuit or in circuit with a relay that is arranged in themotor circuit and thus opens the'power circuit to the motor when thespring 35 has been wound to a predetermined tension. The spring 85 isthus operative to control the operation of the automatic switch.

Mounted on the sub-base of the casing 68 I provide a solenoid I05 havingan armature member I06 which is pivotally connected at I01 with arm I08.Arm I08 is pivoted at I03 on casing Without any current on the solenoidI06 bell crank II6 will be engaged with the lower cam 63, the powercircuit being open through control switch I35. When current is appliedform source I36 by closing switch I35 to the solenoid I05, the solenoidpulls in armature I06 rocking arm I08 (Fig. 3) about its pivot I08 andin turn moving bell crank H6. The movement of bell crank II8 shifts theabutment face II6a thereof from a position aligned with disc face 63b toa position aligned with disc face 62b. It will be observed that disc 63'is the exact counterpart of disc 62. The engaging surface at 6312 iscurved in the manner similar to the curved surface 62b of disc 62. Whensolenoid I05 is deenergized the bell crank II6 drops back by gravity toa position in which the end thereof is aligned with curved face 83b ofdisc 63. The curved surface 62b of disc 62 has the tendency of keepingbell crank I I6 in engagement by confining the end of the bell crank bydrawing the bell crank inwardly rather than forcing the bell crank awaywhich would be the situation if the disc face were flat or radial andnot 68. The angular movement of arm I08 is restricted by bracket memberI I0. A counterweight III is carried by the movable arm I08 and isconnected through spring II2 to the fixed stud Ill on casing 68 thustending to maintain the arm in the full line position illustrated inFig. 3. The arm I08 carries a movable bracket member II5. Bracket memberH5 is bolted to bell crank I I6 which is in turn pivoted at I I1. Theopposite end of the bell crank II6 shown at H8 is movable beneath washermember II8 (Fig. 23) mounted on stud I20 projecting from casing 68. ArmI2I is also mounted on stud I20 and is free to move angularly about studI20. Bell crank I I6 is pivoted on stud I II which is fastened inleverarm I 2I so that when bell crank II6 moves it shifts arm I2I in anangular path and applies a brake band represented at I22 to the brakedrum shown at I23. Brake band I22 is normally loose about drum I23 byaction of spring I2'I pressing against the end of lever arm I2I tendingto slack off on the brake band I22. A spring I24 is arranged to maintainbell crank I I6 against stud I25 which in turn maintains arm I2I in aposition in which brake band I22 is unapplied. However, upon shifting ofthe bell crank II6 against the action of spring I24 when disc 63operated by engagement with curved face II of bell crank II6 the bellcrank moves back imparting motion to lever I2I applying tension to brakeband I22 and establishing frictional contact with brake drum I23. Thelever I2I and bell crank II6 are floating with respect to each other orpin III under tension by spring I20 and as hell crank II6 shifts itimparts motion to lever I2I which in turn increases tension on springI2'I through which stud I26 extends. Stud preformed in a curved face asprovided herein. Thus the spring 85 consituting the spring motor candrive the insulators 5 and 8 to certain predetermined limits determinedby abutment offaces 62b or 63b with face I I6a.

Flywheel I28 is carried by shaft I28 which is journaled at I30 and I3Iin the casing 68 and frame II forming part of sub-base II. The flywheelI28 insures a uniform speed of movement I26 in turn connects to the endof brake band I22 for thereby applying the frictional brake inaccordance with the angular displacement of lever I2I. It will beobserved that bell crank II6 has the end at II6a thereof so shaped thatit is engaged by the curved face 62b of disc 62.

Bell crank II6 has limited angular movement about inclined faces I2Iaand I2") of the lever I2I by reason of the enlarged and curved wallbore' I I6!) and the rocking thereof under control of solenoid I05 forshifting the end to of hell crank II6 'into either theplane of disc 82or disc 63.

of the switch arms when the spring motor becomes effective to movethearms. The shaft I23 carries pinion I32 which meshes with the spider gearwheel I32 that forms part of the spring housing 84.. Shaft I26 extendsbeyond case 68 and carries the brake drum I23 which is engaged by thebrake band I22 operating as hereinbefore explained. The flywheel impartssufficient inertia to the system to retard the spring from excessivespeed of operation when the spring initially takes over control of theswitch arms. v

While I have described my invention in one of its preferred embodiments,I realize that modiflcations may be made in the details and arrangementof the switch system and I desire that it be understood that myinvention is not limited to the particular structures shown but may bechanged as to detail within the scope of the appended claims.

What I claim and desire to secure by Letters Patent of the United Statesis as follows:

1. Control mechanism for electric switches having paths of travelapproximately degrees, means for driving the electric switches insuccessively opposite directions for successive repeat operations inopposite directions, means for driving the aforesaid means comprising aspring motor, a shaft extending from said spring motor to said firstmentioned means, opposed disc members carried by said shaft and havingnotches therein, an anguiarly shiftable pawl selectively movable intothe path of either of the notches on said disc members and electricallyactuated means for alternately shifting said pawl into the path of thenotches on said respective disc members for forming a limiting abutmentfor the travel of said switches in either of the opposite directions andmeans for restoring tension in said spring motor.

2. Control mechanism comprising driving means, a driving shaft rotatableby said driving means, a driven shaft, reversing means disposed betweensaid driving shaft and said driven shaft for successively operating saiddriven shaft through alternate angular distances of approximately 90degrees, a pair of disc members associated with said driving shaft andhaving notches therein forming stop devices, an angularly displaceablepawl selectively shiftable in abutting position with either of thenotches of said disc members for limiting the travel of said drivingshaft to a position in which the driven shaft completes rotativemovement to a limit of approximately 90 degrees from the initialposition thereof, and electromagnetic means for selectively displacingsaid pawl.

3. Control mechanism comprising driving means, a driving shaft rotatableby said driving means, a driven shaft, means disposed between saiddriving shaft and said driven shaft for successively operating saiddriven shaft through opposite angular distances of approximately 90degrees, a pair of disc members associated with said driving shaft eachhaving stop members in the peripheries thereof, an angulai lydisplaceable pawl selectively shiftable in abutting position with eitherof the stop members of said disc members for limiting the travel of saiddriving shaft 10 to a position in which the driven shaft completesrotative movement to a limit of approximately 90 degrees from theinitial position thereof. electromagnetic means for selectivelydisplacing said pawl, and brake means associated with said driving shaftfor eflectively limiting the driving torque applied to said drivingshaft upon engagement of said pawl with the stop members in either ofsaid disc members.

JOSEPH F. FRESE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 541,543 Hcrdman June 25, 1895645,103 Jones Mar. 13, 1900 1,029,993 Cheney June 11, 1912 1,123,282Harris Jan. 5, 1915 1,554,718 Dryer Sept. 22, 1925 1,740,405 KearsleyDec. 17, 1929 1,959,522 Builard May 22, 1934 2,311,714 Thompson et al.Feb. 23, 1943

